Benthic foraminiferal morphogroups from the Paleocene of the coastal part of East Stara Planina Mts.

Abstract

Twelve morphogroups were defined on the basis of test shape and nature of test coiling as a result of the investigation of the Paleocene benthic foraminifera from the coastal part of East Stara Planina. The morphogroups are rounded trochospiral (RT), plano-convex trochospiral (PT), biconvex trochospiral (BT), milioline (M), rounded planispiral (RP), lenticular (L), flattened ovoid (FO), tapered and cylindrical (T/C), spherical (S), flattened tapered (FT), tubeshaped (T), streptospiral and heteromorphous (S/H). The previously described Byala-type and Flysh-type assemblages differ from each other by the predominant test morphology. There is no strongly dominating morphogroup in the Byala-type, while the Flysh-type is strongly dominated by two morphogroups. Both Byala-type and Flysh-type are dominated by morphogroups typical for deep sea conditions.